1. Field of the Invention
The present invention relates to a winged injection needle having needle covering means, comprising at least a needle tube for puncturing, a spherical hub for holding the base end of the needle tube, a hollow needle-housing member for allowing the hub to be displaced by sliding and allowing the entirety of the needle tube for puncturing and the hub to be housed within the lumen of the needle-housing member by the displacement, a pair of flexible wings projectingly formed on left and right outer faces of the hollow needle-housing member, and a guide tube connected to the hub.
2. Description of the Prior Art
(1) Conventionally, in medical institutions contamination and infection caused by erroneous puncture of an injection needle, a puncture needle, etc. have been problems and, in particular, since there has been increasing social concern about hepatitis, AIDS, etc. in recent years, attention is being given to means for actively preventing accidents such as erroneous puncture. However, since the medical institutions are also being urged to cut medical costs, the means and methods for preventing contamination and infection have not been developed as was expected.
In the past, various covers and means have been devised for making it difficult to cause an erroneous puncture when housing an injection needle or a puncture needle after use. Although they include not only covers for winged injection needles but also those for simple injection needles, the present invention discloses covering means for a winged injection needle, which is often used for treatment involving infusion, blood transfusion or extracorporeal blood circulation.
(2) Much publicly-known technology has been disclosed regarding means for safely housing a winged injection needle after use, and it is mainly those having a simple constitution that will be exemplified.
The winged injection needle is formed from an injection needle, a needle base to which the needle is fixed, and a guide tube that is connected to the needle base, and many of the erroneous puncture prevention means are constructed so that the injection needle and the needle base can move relative to each other so as to prevent an erroneous puncture after use.
Conventionally known winged injection needles can be broadly classified into two types; those in which the wing is attached to the injection needle or the needle base, and those in which the wing is attached to a cover.
(a) Examples of the former are disclosed in JP, B, 6-7861, JP, A, 8-206195, JP, B, 4-36026, JP, A, 4-261665, JU, B, 5-22182, etc.
(b) Examples of the latter are disclosed in JP, B, 6-7861 (both types are disclosed), JP, B, 2535342, etc.
However, the above-mentioned disclosed means for preventing erroneous puncture are not completely satisfactory from an overall viewpoint, which includes operability, safety, simple structure, cost reduction and hygienic disposal after use.
A winged needle disclosed in JP, B, 6-7861, in which a wing is formed on a protector, has a simple mechanism and is more advantageous in comparison with other erroneous puncture prevention instruments. However, since this erroneous puncture prevention instrument has some defects as described below, attempts have been made to improve it.
That is to say, in the above-mentioned example, it is necessary to form a protrusion and a recess on both a hub and the protector in order to reliably regulate the position of the needle at an exposed position and a housed position, and positioning and adjustment of the dimensions need to be devised. Furthermore, in order for there to be easy and reliable latching when using and housing the puncture needle, it is desirable that engaging means is formed on the entire outer surface of the hub or the entire lumen of the protector, but this makes the structure complicated and increases the production cost. Furthermore, since a tightly-fitting structure is provided so that the needle hub does not move easily within the protector when puncturing and when housing, there is the defect that it is difficult to move the protector smoothly when sliding it.
Furthermore, for many of the conventional winged injection needles disclosed in JP, B, 6-7861, etc. there is the possibility that, when disposing of an injection needle after use, the liquid drug preparation or blood remaining in the needle or tube might leak and contaminate the operator's hand. That is to say, there is the problem that they cannot be disposed of safely.